织物升温速率对活性染料轧-蒸无盐染色的影响

Influence of fabric heating rate on salt-free pad-steam dyeing of reactive dye

针对活性染料轧-蒸染色固色率低的问题,通过测试湿织物热常数探究织物表面温度变化规律,分析了染液组成和带液率对织物热常数、升温速率及染色性能的影响,研究了织物升温速率对活性染料染色性能的影响。结果表明:添加硫酸钠能够促进织物升温,提高染色织物的K/S值和固色率,但不符合无盐染色的要求;增加带液率,湿织物导热系数和容积热容随之增大,而表面温度却呈现降低趋势;染料固色率与织物表面升温速率变化规律一致,说明提高织物升温速率有助于改善活性染料染色性能;降低织物带液率可提高升温速率,是实现无盐染色的有效途径。

In order to enhance the dye fixation rate of reactive dye in pad-steam dyeing process, the influence of the fabric heating rate on the dyeing properties of reactive dye was investigated to search the method of salt-free dyeing with high fixation rates. The temperature of fabric in the steaming process was calculated using the thermal conductivity and volumetric heat capacity measured. The influence of dye liquor composition and fabric pickup on the variation of fabric temperature was investigated. Besides, the color performance and fastness of the dyed fabrics as well as the dye fixation rates were studied. The results indicate that the fabric heating rates are increased by adding the Na2SO4 into padding solutions, thereby enhancing K/S value and dye fixation rate. However, it does not meet requirements of the salt- free dyeing. Increasing the pickup resulted in increasing the thermal conductivity and volumetric heat capacity of fabrics, but decreasing the temperature of fabric. The K/S value of dyed fabrics and the dye fixation rates increased as the fabric pickups decreased, which is substantially in accordance with the variation of the fabric heating rates. The phenomenon confirmes that enhancing fabric heating rates is conducive to improve the dyeing properties of reactive dye. Reducing the fabric pickup can increase the fabric heating rates, which is an effective way to realize salt-free dyeing in continuous pad-steam dyeing.